Bsrgvty

I had previously installed wine-stable, but for a particular program I wanted to run it was recommended that I run wine-staging. So I uninstalled wine-stable, and tried to install wine-staging as normal.

When I run

sudo apt install wine-staging

I get

 Reading package lists... Done
Building dependency tree 
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help resolve the situation:

The following packages have unmet dependencies:
 wine-staging : Depends: wine-staging-amd64 (= 4.0~rc7~cosmic) but it is not going to be installed
 Depends: wine-staging-i386 (= 4.0~rc7~cosmic)
E: Unable to correct problems, you have held broken packages.

So when I try to install the dependencies, I just keep on getting further down a rabbit hole of things I need but for some unexplained reason cannot install.

So for instance, when I tried to install wine-staging-amd64, I get

Reading package lists... Done
Building dependency tree 
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help resolve the situation:

The following packages have unmet dependencies:
 wine-staging-amd64 : Depends: libavcodec58 (>= 7:4.0) but it is not installable
 Depends: libavutil56 (>= 7:4.0) but it is not installable
 Depends: libvkd3d1 but it is not installable
E: Unable to correct problems, you have held broken packages.

This is mainline Ubuntu, on an installation less than a week old. I haven't done any messing with my repos, and I've spent the past hour reading all kinds of solutions that seemed to work for everybody else, but do not work for me, such as sudo dpkg --add-architecture i386. I've tried installing the .deb directly from the winehq website, but Ubuntu Software install progress just goes from 0-100 in a second like it's installed, and then presents me with the install button again with no error indicating something went wrong. With gdebi, it tells me it's got a dependency that cannot be satisfied - which is itself. I'm not a new Linux user, and I've never run into such a ridiculous web of issues trying to install a simple package. Is there something going on within the WINE project right now, or am I somehow doing something wrong? This issue is seriously testing my patience.

I had similar issue. I forgot to add the wine repository key.

$ wget -qO- https://dl.winehq.org/wine-builds/Release.key | sudo apt-key add -

then add the repository

$ sudo apt-add-repository 'deb http://dl.winehq.org/wine-builds/ubuntu/ bionic main'

and install your flavor of wine

$ sudo apt install winehq-staging

or $ sudo apt install winehq-stable

Checkout the new version

$ wine --version
wine-4.0

I just fixed the exact same problem. I had the complete same output as you. I followed Vic's answer. It failed but not because his answer was inadequate but because I had multiple sources for wine in my
/etc/apt/sources.list.d/additional-repositories.list. Before you do the nuclear option check to see if your additional sources list might have conflicting wine repos. If you do, remove them all and then do Vic's answer to add the correct repo|key and install what you need.